1. Field Of The Invention
This invention relates to a method and apparatus for removing hazardous particulate material from a recirculating solvent which is used in an article cleaning system.
2. Description Of The Prior Art
When solvents are used to remove hazardous particles from articles, the articles and the solvents must be isolated from the operators and the environment lest the operators be injured by exposure to the solvent or to the particulate material. It is not desirable to permit spent solvent to drain in an uncontrolled fashion from the system since the hazardous material which is entrained in the solvent will contaminate everything that comes in contact with it. Accordingly, when removing hazardous particulate material such as radioactive particles and the like, it is desirable that the solvent be cleaned and recirculated for reuse rather than be discharged from the system while the radioactive material is contained therein.
A solvent such as trichlorotriflouroethane which is sold under the trademark FREON TF or FREON 113 is particularly suitable for cleaning articles. Since it boils at temperatures just above room temperature, it can be easily cleaned by distillation.
With the foregoing in mind, it would be desirable to have an efficient and reliable method and apparatus for recovering solvent from a cleaning chamber and removing the particles of hazardous material which are suspended or disolved in the solvent so that the solvent can be reused.
Additionally, it is advantageous to have a system where the solvent can be recovered continuously as it is being recirculated.
Still further, it would be desirable if such a system included a means for storing solvent when the apparatus is not in use and in which the stored solvent is free of hazardous particulate material.
Typical devices of the prior art which are used for cleaning materials which may be coated with hazardous particulate material are shown in U.S. Pat. No. 4,443,269 which issued on Jan. 22, 1981, to Joseph A. Capella and David E. Fowler and U.S. Pat. No. 4,235,600 which issued on Nov. 25, 1980, to Joseph A. Capella and Dennis R. Morrison.